panic(ffffffff82267a81) at panic+0x15c sys/kern/subr_prf.c:207 pool_do_get(ffffffff826529e8,2,ffff800020a38778) at pool_do_get+0x439 sys/kern/subr_pool.c:738 pool_get(ffffffff826529e8,2) at pool_get+0xeb sys/kern/subr_pool.c:581 m_copym(fffffd807c431d00,264,66,2) at m_copym+0x174 m_get sys/kern/uipc_mbuf.c:250 [inline] m_copym(fffffd807c431d00,264,66,2) at m_copym+0x174 sys/kern/uipc_mbuf.c:667 tcp_output(ffff800000a06ba0) at tcp_output+0x15ba sys/netinet/tcp_output.c:673 tcp_input(ffff800020a38d58,ffff800020a38d64,6,2) at tcp_input+0x2353 ip_deliver(ffff800020a38d58,ffff800020a38d64,6,2) at ip_deliver+0x353 sys/netinet/ip_input.c:668 ip_ours(ffff800020a38d58,ffff800020a38d64,ffff800020a189c0,0) at ip_ours+0x412 ip_input_if(ffff800020a38d58,ffff800020a38d64,4,0,ffff800000679800) at ip_input_if+0x6ce ipv4_input(ffff800000679800,fffffd8066bc7c00) at ipv4_input+0x48 sys/netinet/ip_input.c:215 if_input_local(ffff800000679800,fffffd8066bc7c00,2) at if_input_local+0xf9 sys/net/if.c:776 loinput(ffff800000679800,fffffd8066bc7c00,0) at loinput+0x4f sys/net/if_loop.c:239 if_input_process(ffff800000679800,ffff800020a38ec8) at if_input_process+0xfb if_ih_input sys/net/if.c:909 [inline] if_input_process(ffff800000679800,ffff800020a38ec8) at if_input_process+0xfb sys/net/if.c:943 end trace frame: 0xffff800020a38f10, count: 0 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs. ddb{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic pool_do_get: mbufpl free list modified: page 0xfffffd80671df000; item addr 0xfffffd80671dfa00; offset 0x0=0x6718450000000000 != 0x6718453d968e98df ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff82267a81) at panic+0x15c sys/kern/subr_prf.c:207 pool_do_get(ffffffff826529e8,2,ffff800020a38778) at pool_do_get+0x439 sys/kern/subr_pool.c:738 pool_get(ffffffff826529e8,2) at pool_get+0xeb sys/kern/subr_pool.c:581 m_copym(fffffd807c431d00,264,66,2) at m_copym+0x174 m_get sys/kern/uipc_mbuf.c:250 [inline] m_copym(fffffd807c431d00,264,66,2) at m_copym+0x174 sys/kern/uipc_mbuf.c:667 tcp_output(ffff800000a06ba0) at tcp_output+0x15ba sys/netinet/tcp_output.c:673 tcp_input(ffff800020a38d58,ffff800020a38d64,6,2) at tcp_input+0x2353 ip_deliver(ffff800020a38d58,ffff800020a38d64,6,2) at ip_deliver+0x353 sys/netinet/ip_input.c:668 ip_ours(ffff800020a38d58,ffff800020a38d64,ffff800020a189c0,0) at ip_ours+0x412 ip_input_if(ffff800020a38d58,ffff800020a38d64,4,0,ffff800000679800) at ip_input_if+0x6ce ipv4_input(ffff800000679800,fffffd8066bc7c00) at ipv4_input+0x48 sys/netinet/ip_input.c:215 if_input_local(ffff800000679800,fffffd8066bc7c00,2) at if_input_local+0xf9 sys/net/if.c:776 loinput(ffff800000679800,fffffd8066bc7c00,0) at loinput+0x4f sys/net/if_loop.c:239 if_input_process(ffff800000679800,ffff800020a38ec8) at if_input_process+0xfb if_ih_input sys/net/if.c:909 [inline] if_input_process(ffff800000679800,ffff800020a38ec8) at if_input_process+0xfb sys/net/if.c:943 ifiq_process(ffff800000679bf8) at ifiq_process+0x80 sys/net/ifq.c:646 taskq_thread(ffff80000002b080) at taskq_thread+0x9c sys/kern/kern_task.c:369 end trace frame: 0x0, count: -16 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff800020a385c0 rbx 0xffff800020a38670 rdx 0xffff800020a189c0 rcx 0 rax 0 r8 0xffffffff8124a8ef kprintf+0x16f r9 0x1 r10 0x25 r11 0x4e994adb3a42d039 r12 0x3000000008 r13 0xffff800020a385d0 r14 0x104 r15 0x1 rip 0xffffffff811a6058 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020a385b0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (softnet) pid=22574 stat=onproc flags process=14000 proc=200 pri=32, usrpri=51, nice=20 forw=0xffffffffffffffff, list=0xffff800020a18c30,0xffff800020a18760 process=0xffff800020a1a3c0 user=0xffff800020a34000, vmspace=0xffffffff82651870 estcpu=1, cpticks=3, pctcpu=0.0 user=0, sys=3, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 40601 445957 56141 0 2 0 syz-executor.0 40601 498968 56141 0 3 0x4000080 fsleep syz-executor.0 40601 428716 56141 0 7 0x4000000 syz-executor.0 16642 113692 0 0 3 0x14200 acct acct 45429 507963 1 0 3 0x100083 ttyin getty 80541 24454 14414 0 3 0x82 nanosleep syz-executor.1 56141 372749 14414 0 3 0x82 nanosleep syz-executor.0 36154 453269 0 0 3 0x14200 bored sosplice 14414 347788 15104 0 3 0x82 kqread syz-fuzzer 14414 193560 15104 0 3 0x4000082 thrsleep syz-fuzzer 14414 182817 15104 0 3 0x4000082 thrsleep syz-fuzzer 14414 477905 15104 0 3 0x4000082 thrsleep syz-fuzzer 14414 319475 15104 0 3 0x4000082 thrsleep syz-fuzzer 14414 450138 15104 0 3 0x4000082 thrsleep syz-fuzzer 14414 417036 15104 0 3 0x4000082 thrsleep syz-fuzzer 14414 449516 15104 0 3 0x4000082 thrsleep syz-fuzzer 14414 353342 15104 0 3 0x4000082 thrsleep syz-fuzzer 14414 5410 15104 0 3 0x4000082 thrsleep syz-fuzzer 15104 427273 19961 0 3 0x10008a pause ksh 19961 443014 47777 0 3 0x92 select sshd 47777 403743 1 0 3 0x80 select sshd 1991 219987 50242 74 3 0x100092 bpf pflogd 50242 117792 1 0 3 0x80 netio pflogd 44359 327529 21381 73 3 0x100090 kqread syslogd 21381 302002 1 0 3 0x100082 netio syslogd 13053 2945 1 77 3 0x100090 poll dhclient 38690 221650 1 0 3 0x80 poll dhclient 96005 345468 0 0 3 0x14200 bored smr 71780 201970 0 0 3 0x14200 pgzero zerothread 22361 58686 0 0 3 0x14200 aiodoned aiodoned 57810 517997 0 0 3 0x14200 syncer update 2816 522436 0 0 3 0x14200 cleaner cleaner 98797 34964 0 0 3 0x14200 reaper reaper 33569 453385 0 0 3 0x14200 pgdaemon pagedaemon 69069 167651 0 0 3 0x14200 bored crynlk 60782 192521 0 0 3 0x14200 bored crypto 47520 282190 0 0 3 0x40014200 acpi0 acpi0 30364 427279 0 0 3 0x40014200 idle1 *71698 22574 0 0 7 0x14200 softnet 26359 511546 0 0 3 0x14200 bored systqmp 31584 364489 0 0 3 0x14200 bored systq 84446 118293 0 0 3 0x40014200 bored softclock 54011 267185 0 0 3 0x40014200 idle0 1 213227 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks CPU 0: exclusive mutex mbufpl r = 0 (0xffffffff826529f8) #0 witness_lock+0x52e sys/kern/subr_witness.c:1164 #1 mtx_enter_try+0x102 #2 mtx_enter+0x4b sys/kern/kern_lock.c:266 #3 pool_get+0xbf sys/kern/subr_pool.c:578 #4 m_gethdr+0x4c sys/kern/uipc_mbuf.c:283 #5 tcp_output+0x14e6 #6 tcp_usrreq+0x629 sys/netinet/tcp_usrreq.c:373 #7 sosend+0x671 sys/kern/uipc_socket.c:549 #8 sendit+0x52b sys/kern/uipc_syscalls.c:657 #9 sys_sendto+0x80 sys/kern/uipc_syscalls.c:522 #10 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #10 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #11 Xsyscall+0x128 Process 40601 (syz-executor.0) thread 0xffff800020ac69d8 (428716) exclusive rwlock netlock r = 0 (0xffffffff824de498) #0 witness_lock+0x52e sys/kern/subr_witness.c:1164 #1 solock+0x5a sys/kern/uipc_socket2.c:282 #2 sosend+0x559 sys/kern/uipc_socket.c:537 #3 sendit+0x52b sys/kern/uipc_syscalls.c:657 #4 sys_sendto+0x80 sys/kern/uipc_syscalls.c:522 #5 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #5 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #6 Xsyscall+0x128 Process 71698 (softnet) thread 0xffff800020a189c0 (22574) shared rwlock softnet r = 0 (0xffff80000002b0e0) #0 witness_lock+0x52e sys/kern/subr_witness.c:1164 #1 taskq_thread+0x8f sys/kern/kern_task.c:368 #2 proc_trampoline+0x1c ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9558 6429K 7446K 78643K 11346 0 pcb 13 9K 9K 78643K 340 0 rtable 96 3K 4K 78643K 657 0 ifaddr 113 22K 22K 78643K 309 0 counters 43 33K 34K 78643K 107 0 ioctlops 0 0K 4K 78643K 1548 0 iov 0 0K 16K 78643K 171 0 mount 1 1K 1K 78643K 1 0 vnodes 1227 77K 78K 78643K 1821 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 17 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 702 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 5 13K 25K 78643K 1085 0 sigio 0 0K 0K 78643K 99 0 proc 62 63K 95K 78643K 623 0 subproc 32 2K 2K 78643K 71 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 1K 78643K 256 0 in_multi 136 5K 5K 78643K 362 0 ether_multi 1 0K 0K 78643K 61 0 mrt 0 0K 0K 78643K 7 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 115 519K 519K 78643K 115 0 exec 0 0K 1K 78643K 324 0 pfkey data 0 0K 0K 78643K 2 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 7 26K 26K 78643K 7 0 UVM amap 173 275K 275K 78643K 4862 0 UVM aobj 108 4K 4K 78643K 116 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 230 0 NDP 16 0K 0K 78643K 60 0 temp 148 3031K 3098K 78643K 39672 0 kqueue 3 4K 20K 78643K 194 0 SYN cache 2 16K 16K 78643K 2 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 21 0 11 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 109 0 107 1 0 1 1 0 8 0 rtentry 112 112 0 74 2 0 2 2 0 8 0 unpcb 120 732 0 722 1 0 1 1 0 8 0 syncache 264 19 0 19 6 5 1 1 0 8 1 sackhl 24 2 0 2 1 1 0 1 0 8 0 tcpqe 32 241 0 241 3 3 0 1 0 8 0 tcpcb 544 674 0 667 3 2 1 2 0 8 0 inpcb 280 2586 0 2572 9 4 5 5 0 8 3 rttmr 72 2 0 2 2 2 0 1 0 8 0 nd6 48 17 0 12 1 0 1 1 0 8 0 pkpcb 40 8 0 8 4 4 0 1 0 8 0 ppxss 1128 3 0 3 3 3 0 1 0 8 0 pffrag 232 17 0 16 5 4 1 1 0 482 0 pffrnode 88 17 0 16 5 4 1 1 0 8 0 pffrent 40 601 0 587 6 5 1 1 0 8 0 pfosfp 40 846 0 423 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfstitem 24 132 0 68 1 0 1 1 0 8 0 pfstkey 112 132 0 68 2 0 2 2 0 8 0 pfstate 328 132 0 68 6 0 6 6 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 540 0 340 16 3 13 13 0 8 0 art_table 32 541 0 340 2 0 2 2 0 8 0 art_node 16 111 0 80 1 0 1 1 0 8 0 sysvmsgpl 40 57 0 30 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 700 0 690 1 0 1 1 0 8 0 shmpl 112 114 0 10 3 0 3 3 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 3248 0 1843 46 0 46 46 0 8 0 ffsino 272 3248 0 1843 95 0 95 95 0 8 0 nchpl 144 5382 0 3774 61 0 61 61 0 8 0 uvmvnodes 72 3438 0 0 63 0 63 63 0 8 0 vnodes 208 3438 0 0 181 0 181 181 0 8 0 namei 1024 18802 0 18802 1 0 1 1 0 8 1 percpumem 16 64 0 32 1 0 1 1 0 8 0 vcpupl 1984 30 0 0 4 0 4 4 0 8 0 vmpool 560 33 0 3 3 0 3 3 0 8 0 scsiplug 64 4 0 4 3 3 0 1 0 8 0 scxspl 192 15036 0 15036 13 10 3 6 0 8 3 plimitpl 152 103 0 95 1 0 1 1 0 8 0 sigapl 424 1298 0 1265 4 0 4 4 0 8 0 futexpl 56 26984 0 26983 1 0 1 1 0 8 0 knotepl 112 354 0 335 1 0 1 1 0 8 0 kqueuepl 144 1104 0 1101 1 0 1 1 0 8 0 pipelkpl 48 350 0 340 1 0 1 1 0 8 0 pipepl 120 700 0 681 3 1 2 2 0 8 1 fdescpl 496 1281 0 1265 3 0 3 3 0 8 0 filepl 152 14224 0 14120 13 6 7 8 0 8 2 lockfpl 104 301 0 300 1 0 1 1 0 8 0 lockfspl 48 98 0 97 1 0 1 1 0 8 0 sessionpl 112 22 0 11 1 0 1 1 0 8 0 pgrppl 48 34 0 23 1 0 1 1 0 8 0 ucredpl 96 3494 0 3484 1 0 1 1 0 8 0 zombiepl 144 1265 0 1264 1 0 1 1 0 8 0 processpl 960 1298 0 1264 5 0 5 5 0 8 0 procpl 624 3892 0 3847 5 1 4 5 0 8 0 sosppl 128 15 0 15 5 5 0 1 0 8 0 sockpl 400 3468 0 3446 14 7 7 7 0 8 4 mcl64k 65536 20 0 0 3 0 3 3 0 8 0 mcl16k 16384 3 0 0 1 0 1 1 0 8 0 mcl12k 12288 13 0 0 2 0 2 2 0 8 0 mcl9k 9216 2 0 0 1 0 1 1 0 8 0 mcl8k 8192 5 0 0 1 0 1 1 0 8 0 mcl4k 4096 9 0 0 2 0 2 2 0 8 0 mcl2k2 2112 5 0 0 1 0 1 1 0 8 0 mcl2k 2048 154 0 0 19 1 18 19 0 8 0 mtagpl 80 14 0 0 1 0 1 1 0 8 0 mbufpl 256 750 0 0 42 0 42 42 0 8 0 mbufpl: pool(0xffffffff826529e8:mbufpl): free list modified: page 0xfffffd80671df000; item ordinal 0; addr 0xfffffd80671dfa00 (p 0xfffffd80634f0000); offset 0x0=0x6718450000000000 bufpl 280 6913 0 646 448 0 448 448 0 8 0 anonpl 16 143915 0 126265 115 27 88 88 0 124 15 amapchunkpl 152 8814 0 8669 44 30 14 20 0 158 6 amappl16 192 6882 0 5906 92 34 58 61 0 8 8 amappl15 184 413 0 410 1 0 1 1 0 8 0 amappl14 176 4 0 2 2 1 1 1 0 8 0 amappl13 168 50 0 47 1 0 1 1 0 8 0 amappl12 160 290 0 289 2 1 1 1 0 8 0 amappl11 152 327 0 308 1 0 1 1 0 8 0 amappl10 144 106 0 100 1 0 1 1 0 8 0 amappl9 136 390 0 387 1 0 1 1 0 8 0 amappl8 128 386 0 351 2 0 2 2 0 8 0 amappl7 120 219 0 206 1 0 1 1 0 8 0 amappl6 112 273 0 270 2 1 1 1 0 8 0 amappl5 104 1189 0 1172 1 0 1 1 0 8 0 amappl4 96 554 0 520 2 0 2 2 0 8 0 amappl3 88 150 0 145 1 0 1 1 0 8 0 amappl2 80 9923 0 9846 3 1 2 3 0 8 0 amappl1 72 37989 0 37542 26 16 10 20 0 8 0 amappl 80 4212 0 4147 2 0 2 2 0 84 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma256 256 6 0 6 1 1 0 1 0 8 0 dma128 128 253 0 253 1 1 0 1 0 8 0 dma64 64 6 0 6 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 18 0 17 1 0 1 1 0 8 0 aobjpl 64 115 0 8 2 0 2 2 0 8 0 uaddrrnd 24 1314 0 1268 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1314 0 1268 1 0 1 1 0 8 0 vmmpekpl 168 13892 0 13849 3 0 3 3 0 8 1 vmmpepl 168 165220 0 163024 185 74 111 132 0 357 10 vmsppl 368 1313 0 1268 5 0 5 5 0 8 0 pdppl 4096 2636 0 2566 10 0 10 10 0 8 0 pvpl 32 427619 0 406780 248 41 207 207 0 265 34 pmappl 232 1313 0 1268 3 0 3 3 0 8 0 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 225 0 17 6 0 6 6 0 8 0